The present invention relates to a device according to the preamble of claim 1.
Known soap and foam dispensers (inter alia EP-B1-0 019 582) have supply bottles for a soap solution (emulsion, dispersion, etc.) which are placed upside down in an intermediate container which maintains a relatively constant level of liquid in the manner of a birds"" drinking vessel in order to feed a downstream metering device.
It has been found that during the operation of such a dispenser the intermediate container is contaminated by impurities in the atmosphere and that after more or less long use such a dispenser has a high germ count and therefore, instead of serving to clean hands, it also contaminates them.
The above-mentioned problems represent a great risk owing to the increasing number of infectious diseases, especially in factories and organizations that manufacture and/or distribute foodstuffs, or in the health sector (hospitals, etc.).
It has also been found to be disadvantageous that known dispensersxe2x80x94in the often very limited lighting conditions of wash-roomsxe2x80x94have an inadequate filling-level indicator, so that such dispensers are often without a continuous flow of soap solution which of course also greatly impairs hygiene conditions.
Furthermore, an empty intermediate container is a receiving reservoir for countless germs which remain in the system or multiply therein even when a fresh supply container is subsequently inserted.
In addition, the market offers various qualities of soap which, depending on teir purpose, are suitable only for specific dispensers and places of use. For example, soap solutions that are used in sectors requiring a high level of hygiene contain anti-bacterial additives and soap solutions that are used in other sectors contain fat-replenishing active substances and/or perfumes. Furthermore, foam dispensers require soap solutions having different physical properties, especially a higher viscosity, from those necessary, for example, in soap dispensers.
In the past, therefore, dispensers were often equipped with unsuitable soap solutions or supply bottles that were intended for other dispensers and/or places of use.
The object of the invention is to remove those disadvantages and to avoid the risks indicated, that is to say, the hygiene conditions in the dispenser are to be improved and the supply containers are not to be confused.
At the same time, indication of the necessity to replace the supply container is to be improved so that a dispenser which is running dry is recognized in good time. The reserve is also to be sufficiently large to prevent any interruption in operation.
A further object is to provide a device which prevents appliances from becoming contaminated before their first use, for example during dispatch or storage. The problem is solved by the features of patent claim 1; claim 1 characterizes the operating state.
The device according to the invention prevents the use of unsuitable supply containers, that is to say, such containers cannot even be opened by the dispenser because the piercing sleeve does not project into the region of the diaphragm of a container that does not fit.
The resiliently supported closing plug prevents the penetration of impurities into the intermediate container, on the one hand, before the insertion of a supply bottle and, on the other hand, also when that bottle is exchanged or removed, because the closing plug recloses the inlet to the intermediate container without delay.
In addition, a liquid level having a relatively large surface is established in the intermediate container, as a result of which a very narrow labyrinthine edge opening to the surrounding atmosphere is quite sufficient to obtain the effect of a xe2x80x9cbirdsxe2x80x9d drinking vesselxe2x80x9d.
Developments of the subject-matter of the invention are described in the following dependent claims.
A form of keying according to claim 2 is economical because it can also be produced for a standard bottle in numerous non-confusable variants.
The construction of the keying members in the form of ring segments is favorable from the point of view of production technology.
The form according to claim 4 is space-saving and requires only a small amount of material, that is to say, the closing cover carrying it can be very thin-walled. Furthermore, a raised edge facilitates the insertion of a keyed neck of a bottle.
The use of webs and recesses increases the possible combinations considerably.
Especially in the case of more highly viscous soap solutions, the form according to claim 6 ensures a defined position and a corresponding opening angle of the closing plug.
A labyrinthine air inlet prevents the penetration of germs and lets in only as much air as the amount of liquid removed.
The form of the filling-level indicator according to claim 8 gives very good optical conditions and permits the favorable arrangement thereof at the dispenser housing.
A float can be guided by an upright guide strip in an especially simple and operationally reliable manner.
Lateral guide strips according to claim 10 prevent the float from tilting.